Adjustable eccentric



Aug. 2, 1949. o. DOUTT 2,477,581

' ADJUSTABLE ECCENTRIC Filed May 6, 1946 WAIIIH INVENTORL OLIVER oourr AT TORNE' Y Patented Aug. 2, 1949 UNITED STATES PATENT OFFICE ADJUSTABLEECCENTRIC Oliver Doutt, Bremerton, Wash.

Application May 6, 1946, Serial No. 667,553

6 claims. (01. 164-106) (Granted under the act of March 3, 1883, asamended April 30, 1928; 3'70 0. G. 757) This invention refers to anadjustable eccentrio and more specifically to a safety punch presshaving an adjustable eccentric for varying the stroke thereof.

An object of this invention is to provide a new and improved adjustableeccentric.

Another object of this invention is to provide a new and improved safetypunch press having an adjustable eccentric so that the clearance betweendie and punch can be adjusted to just receive the work and exclude thehands of the workman.

Another object of this invention is to provide a punch press having anadjustable stroke of economical, new, and improved design.

Another object of this invention is to provide apparatus substantiallyas shown and described.

In accomplishing these and other objects of the present invention, Ihave provided improved details of structure, the preferred form of whichis illustrated in the accompanying drawings, wherein:

Fig. 1 is a front elevational view of the punch press and eccentric.

Fig. 2 is a transverse section of the eccentric with the locking ringremoved and an adjusting key in place.

There is shown a die I and a punch ll raised a distance l2 above saiddie through the action of a rotating eccentric I3. The punch H isactuated in the conventional manner by the eccentric is through aconnecting rod l4, annular bearing strap l5, and a pivotable connection(not shown) such as a ball and socket joint within the usual crossheadIS, A screw adjustment for varying the length of the connecting rod isshown at H with a set screw Ill.

The eccentric I3 is of variable eccentricity and is shown at its maximumeccentricity and with the connecting red at the top of its stroke in theposition to bring punch H to its greatest height.

To permit of varying its eccentricity, the variable eccentric I3 is madeup of two eccentrics, one inside of the other. The main or primaryeccentric comprises a circular disk I9 having an axially extendedconcentric cylindrical portion 20 perimetrically toothed as at 2| and aneccentrically placed bore 22 with keyway 23 for keying the eccentric tothe drive shaft 24.

A secondary eccentric in the form of an eccentric ring 25, with shoulder26, is journalled on the circular disk I!) of the primary eccentric andjournalled within the annular bearing strap IS. The shoulder 26 abutsagainst the back side 2 of the annular bearing strap l5. Formed withinsaid eccentric 25 is a key hole 21 placed beyond the gear teeth ofprimary eccentric l9 when said two eccentrics are in working assembly.

An adjusting key 28, having a handle and gear teeth 29 of a size to meshwith gear teeth 2| of primary eccentric or disk l9 when nipple 3|] isplaced in key hole 21, is shown in operating position in Fig. 2 and isused to rotate the eccentrics l9 and 25 relative to each other.

A locking ring 3| shown detached in Fig. 2 but in looking position inFig. 1 is an eccentrically bored ring internally toothed as at 32 tomesh with the teeth 2| of primary eccentric or disk [9. The ring 3| isprovided with holes through which extend bolts 33 to engagecorresponding threaded opening-s in the secondary eccentric 25. Thus theteeth 2| and the teeth 32 form a detachable coupling for locking the twoeccentrics I9 and 25 to rotate together. The strap I5 is prevented fromundesired axial movement by being held between locking ring 3| andshoulder 26.

Operation In the operation of the punch press it is desirable to adjustthe length of the stroke for different thicknesses .of material so thatthe punch is raised above the die to a height just sufficient to allowthe insertion of the material to be worked, and thereby give increasedsafety to the operator in that it assists an avoidance of finger injury.

To make this adjustment the locking ring 3| is removed by loosening thebolts 33 and the key 28 is inserted in the key hole 21 as shown in Fig.2. Then with the key 28 acting as a driving planet gear, secondaryeccentric 25 as a driven planet carrier, and primary eccentric [9 as afixed sun gear the two eccentrics are rotated relative to each other andthe total additive eccentricity of the two eccentrics is varied, therebyto determine the length of the stroke of the press,

While I have shown but one embodiment of my invention, it is apparentthat the device is susceptible to modification without departing fromthe spirit of the invention. I do not wish, therefore, to be limited bythe disclosures set forth, but only by the scope of the appended claims.

The invention described herein may be manufactured and used by or forthe Government of the United States of America for governmental purposeswithout the payment of any royalties thereon or therefor.

I claim:

1. A variable eccentric comprising a connecting rod and annular bearingstrap, an eccentric ring journalled within said strap, said ring havinga key hole axially placed herein for receiving a nipple of a toothedadjusting key, a disk journalled within said eccentric ring having aneccentrically placed bore with key way, a perimetrically toothedshoulder formed as a part of said disk, the teeth on said shouldermeshing with the teeth of the adjusting key when its nipple is placed insaid key hole of the eccentric ring for relative rotation of said diskwith respect to said eccentric ring, and an eccentric detachablecoupling ring internally toothed for meshing with the teeth of said diskand having bolt holes through which bolts may extend to engagecorresponding threaded openings in the eccentric ring for securing thedisk and eccentric ring to rotate together.

2. A variable eccentric comprising a strap, an eccentric ring journalledwithin said strap and having a key hole axially placed therein forreceiving a nipple of a toothed adjusting key, a disk journalled withinsaid eccentric ring having an eccentrically placed drive shaftconnection and an axially extended perimetrically toothed cylindricalportion for meshing with the teeth of the adjusting key when in place insaid key hole for rotation relative to said eccentric ring, and aninternally toothed detachable ring adapted to meshwith teeth on saiddisk and means for securing said detachable ring to said eccentric ringfor coupling the eccentric ring with said disk to rotate together.

3. An adjustable stroke safety punch press comprising a die, a punch, acrosshead, a connecting rod and annular bearing strap, an eccentric ringjournalled within bearing strap having an axially aligned key hole and aplurality of axially aligned threaded openings, a disk journalled withinsaid eccentric ring having a eccentrically placed bore with keyway andhaving an axially extended concentric cylindrical portion perimetricallytoothed, a detachable coupling ring internally toothed adapted to meshwith the teeth of said extended cylindrical portion of said disk andhaving a plurality of extended axially aligned openings correspondingwith the openings in said eccentric ring to receive bolts to secure saiddisk to said eccentric ring to rotate together, an independent adjustingkey having a nipple to fit in said key hole and a gear adapted to meshwith the teeth of said disk upon the removal of said coupling ring forthe relative rotation of said disk with respect to said eccentric ring,thereby to adjust the additive eccentricity of the eccentric ring anddisk to that amount to give just sufficient clearance between the dieand the punch for the insertion of the material to be worked and excludethe operators hands, and a drive shaft keyed to the eccentrically placedbore within the disk.

4. A variable eccentric comprising an eccentric disk member, aneccentric ring member journalled on said disk member and adapted toserve as a bearing for a connecting rod strap, a series ofcircumferentially extending gear teeth on one of said members adapted tomesh with the teeth on a detachable toothed adjusting key, a bearingsurface formed on the other of said members to receive said key inbearing relation, whereby rotation of said key while in engagement withsaid bearing surface and in mesh with said series of gear teeth producesrelative rotation between said members, and means attachable uponremoval of said key for detachably securing said members together toprevent relative rotation thereof.

5. A variable eccentric comprising an eccentric disk member, aneccentric ring member journalled on said disk member and adapted toserve as a bearing for a connecting rod strap, a series ofcircumferentially extending gear teeth on one of said members adapted tomesh with the teeth on a detachable toothed adjusting key, a bearingsurface formed on the other of said members to receive said key inbearing relation, whereby rotation of said key while in engagement withsaid bearing surface and in mesh with said series of gear teeth producesrelative rotation between said members, and means for detachablysecuring said members together to prevent relative rotation thereofincluding an element having teeth adapted to engage with the teeth ofsaid series on said first mentioned member.

6. An adjustable eccentric comprising an eccentric disk, an eccentricring journalled on said disk and adapted to serve as a bearing for aconnecting rod strap, said ring having a bearing surface formed thereonto receive a toothed adjusting key in bearing relation, said disk havinga series of gear teeth extending circumferentially thereon and adaptedto mesh with the teeth on said key when said key is in bearingrelationwith said bearing surface, a locking member having a portion adapted tointerengage with said gear teeth on said disk, and means for detachablysecuring said locking member to said ring whereby said disk and saidring are locked together against relative rotation.

OLIVER DOUTT.

REFERENCES CITED The following referenices are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 459,597 Stiles Sept. 15, 1891667,569 Pechin Feb. 5, 1901 FOREIGN PATENTS Number Country Date 9,453Great Britain Apr. 21, 1909 277,480 Germany Aug. 20, 1914

